Discussion:
Eagle’s syndrome, categorized initially by Dr. Watt Eagle, divides patients into two groups based on the structures compressed or irritated by the styloid complex. The classic form involves cranial nerves 5-trigeminal, 7-facial, 9-glossopharyngeal, and/or 10-vagus, where many providers believe this neuralgia is a type of entrapment syndrome involving the cranial nerves, commonly after tonsillectomy (18). The vascular form involves the internal carotid artery (ICA), external carotid artery (ECA) (15), periarterial sympathetic nerve plexus (19), and the internal jugular vein (IJV) (20,21).
In our patient, we assume that the muscle relaxant weakened the normal muscle tone and weakened its share in neck support. On the other hand, SMT, even in the hands of experienced practitioners, has well-known complications, particularly for the upper cervical segment. Lastly, and the most important, from our perspective, is the presence of an anomalous styloid process that caused the injury to ICA. So, SMT acted as the trigger, firing the anomalous styloid process that acted, in turn, as the bullet, causing injury in the ICA.
Many patients who unknowingly have Eagle’s syndrome pursue physical therapy, massage, medical management, injections, and surgery (22). In fact, practitioners of manipulation, irrespective of their professional training, have consistently claimed that the risk of stroke after manipulation is so small that it should be considered insignificant (23,24). However, three studies described carotid artery dissection and/or stroke after massage (25–27). Another three studies described exercise produced adverse symptoms/events, including arterial dissection (28–30). Another research recommends the avoidance of thrust manipulation, along with relative contraindications for combined flexion/rotation in patients with styloid anomalies, as this has led to carotid dissection in several cases (31).
Our patient presented to us ten days after SMT, and this delay in presentation is also noticed in other studies (6,32–36). Moreover, due to the relative inaccessibility of the distal ICA, we chose the endovascular choice as the endovascular management of carotid artery injury had been previously studied and proved to be safe, effective, and maybe even superior to surgery, particularly in zone I and III neck injuries (37–40).